You can make AlphaZero learn different value function by changing the reward from the game. Game with no reward from draw, more reward from shorter games with more captures creates different value functions.
This was what made the romantic style possible in the first place: humans perform worse under pressure, so they tend to crack once they're put on the ropes.
It's psychologically easier to attack than to defend accurately
AlphaZero would not have trouble finding the (likely fairly dull) winning moves, and certainly wouldn’t see any reason to play such a move itself.